Uplink parallel access method suitable for multi-satellite cooperative communication

Abstract

The invention discloses an uplink parallel access method suitable for multi-satellite cooperative communication, and belongs to the technical field of uplink access of satellite communication. For an area overlapped and covered by a plurality of communication satellites, a user terminal often accesses the nearest satellite according to ephemeris, and a single satellite provides communication service. A plurality of satellites cooperatively provide services for user terminals in an overlapping area, so that the communication quality of the user terminals can be improved, and in order to realize multi-satellite cooperative communication, the user terminals need to access each satellite in the overlapping area, and uplink network access application signaling is generally sent to each satellite in different time slots. According to the uplink access method of the satellite-ground link and the inter-satellite link provided by the invention, the user terminal sends the network access application to one of the satellites, and the satellite synchronously sends the network access information to other satellites in the overlapping coverage area in parallel through the inter-satellite link after receiving the network access signaling, so that the uplink access time slot of the user terminal can be saved, and efficient network access is realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of uplink access of satellite communications, and in particular relates to an uplink access method for multi-satellite cooperative communication, and in particular to an efficient access method for a multi-satellite cooperative communication scenario. Background Art

[0002] For areas with overlapping coverage by multiple communication satellites, user terminals often access the nearest satellite based on the ephemeris, and the communication service is provided by a single satellite. Multiple satellites working together to provide services to user terminals in overlapping areas can improve the communication quality of user terminals. In order to achieve multi-satellite collaborative communication, user terminals need to access each satellite in the overlapping area, and generally send uplink access application signaling to each satellite in different time slots. When there are a large number of satellites in the overlapping area, this traditional serial access method will cause a large amount of uplink access time slot overhead, which is not conducive to the transmission of business information after successful access. Summary of the invention

[0003] In view of this, the present invention proposes an uplink parallel access method suitable for multi-satellite cooperative communication, which aims to reduce the uplink access time slot overhead by utilizing multiple inter-satellite links between multiple satellites to perform inter-satellite parallel transmission of user access information.

[0004] In order to achieve the above-mentioned object of the invention, the technical solution adopted by the present invention is:

[0005] An uplink parallel access method applicable to multi-satellite cooperative communication is used for a user terminal to simultaneously access multiple satellites in an overlapping area through a satellite-to-ground link and an inter-satellite link, assuming that the number of satellites in the overlapping area is N; specifically, the following steps are included:

[0006] (1) The user terminal determines based on the ephemeris that the closest satellite in the overlapping area is satellite 1, and the other satellites are satellites 2 to N;

[0007] (2) The user terminal performs downlink and uplink synchronization of signals to satellite 1;

[0008] (3) After the uplink and downlink synchronization is completed, the user terminal sends an uplink access request to Satellite 1 via the satellite-to-ground link with its own ID information in time slot T1. The onboard network control of Satellite 1 verifies the ID information of the user terminal.

[0009] (4) Satellite 1's onboard network control synchronizes the user terminal ID information to satellites 2 and N's onboard network control via the intersatellite link in time slot T2;

[0010] (5) After receiving the user terminal ID information, the onboard network control from satellite 2 to satellite N verifies the identity and sends a successful user ID information synchronization response to the onboard network control of satellite 1;

[0011] (6) Satellite 1's onboard network control sends N satellite access success response messages to the user terminal in time slot T3;

[0012] At this point, uplink parallel access suitable for multi-satellite collaborative communications is completed.

[0013] The beneficial effects of the present invention are:

[0014] The present invention can make full use of the satellite-to-ground link + inter-satellite link to parallelly process user terminal access information, shorten the uplink access time slot of the user terminal, and is suitable for scenarios with a large number of satellites in collaborative communication in overlapping areas. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The invention is a workflow diagram of an uplink access method suitable for multi-satellite cooperative communication.

[0016] Figure 2 It is the information content transmitted in each time slot. DETAILED DESCRIPTION

[0017] The present invention is described in detail below with reference to the accompanying drawings.

[0018] An uplink parallel access method suitable for multi-satellite cooperative communication, Figure 1 The uplink access process under N satellites is given. Figure 2 The information content transmitted in each time slot is given.

[0019] The method of the present invention makes full use of satellite-to-ground links + inter-satellite links, so that the user terminal can access N overlapping area satellites at the same time; Figure 1 The specific steps shown include:

[0020] (1) The user terminal determines based on the ephemeris that the closest satellite in the overlapping area is satellite 1, and the other satellites are satellite 2 to satellite N.

[0021] (2) The user terminal performs downlink and uplink synchronization of signals to satellite 1.

[0022] (3) After the uplink and downlink synchronization is completed, the user terminal sends an uplink access request to satellite 1 with its own ID information in time slot T1. The onboard network control of satellite 1 verifies the user terminal ID information; Figure 2 As shown, the information content transmitted in time slot T1 includes a frame header, a satellite 1 network control address, a user terminal ID and a frame tail.

[0023] (4) Satellite 1's onboard network control synchronizes the user terminal ID information to satellite 2 and satellite N's onboard network control via the intersatellite link in time slot T2; Figure 2 As shown, the information content transmitted from satellite 2 to satellite N in time slot T2 includes a frame header, a satellite n network control address, a user terminal ID and a frame tail; 2≤n≤N.

[0024] (5) After receiving the user terminal ID information, the onboard network control from satellite 2 to satellite N verifies the identity and sends a successful response to the onboard network control of satellite 1 indicating the synchronization of the user ID information.

[0025] (6) Satellite 1's onboard network control sends N satellite access success response messages to the user terminal in time slot T3; Figure 2 As shown, the information content transmitted in time slot T3 includes a frame header, a user terminal address, an access success response, and a frame tail.

[0026] At this point, the user terminal has completed access to N satellites in the overlapping area, completing uplink parallel access suitable for multi-satellite collaborative communications.

Claims

1. An uplink parallel access method suitable for multi-satellite cooperative communication, used for a user terminal to simultaneously access multiple satellites in an overlapping area through a satellite-to-ground link and an inter-satellite link, assuming that the number of satellites in the overlapping area is N; characterized in that: The specific steps include: (1) The user terminal determines based on the ephemeris that the closest satellite in the overlapping area is satellite 1, and the other satellites are satellites 2 to N; (2) The user terminal performs downlink and uplink synchronization of signals to satellite 1; (3) After the uplink and downlink synchronization is completed, the user terminal sends an uplink access request to Satellite 1 via the satellite-to-ground link with its own ID information in time slot T1. The onboard network control of Satellite 1 verifies the ID information of the user terminal. (4) Satellite 1's onboard network control synchronizes the user terminal ID information to satellites 2 and N's onboard network control via the intersatellite link in time slot T2; (5) After receiving the user terminal ID information, the onboard network control from satellite 2 to satellite N verifies the identity and sends a successful user ID information synchronization response to the onboard network control of satellite 1; (6) Satellite 1's onboard network control sends N satellite access success response messages to the user terminal in time slot T3; At this point, uplink parallel access suitable for multi-satellite collaborative communications is completed.

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